From b7491eba32da1dc11781a56d7457e42d94b2aa5c Mon Sep 17 00:00:00 2001
From: Bart Oldeman <bart@dosemu.org>
Date: Tue, 27 Jan 2004 19:26:58 +0000
Subject: [PATCH] Expand tabs for int21/ah=2,9 even in raw device modes and if
 stdout is redirected. This solves bug 1737 (grep2msg problem) This copy&paste
 exercise is to be cleaned up a bit later!

git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@759 6ac86273-5f31-0410-b378-82cca8765d1b
---
 kernel/chario.c   | 28 +++++++++++++++++++++++++++-
 kernel/inthndlr.c | 11 +++++------
 2 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/kernel/chario.c b/kernel/chario.c
index 12b2e19..9864058 100644
--- a/kernel/chario.c
+++ b/kernel/chario.c
@@ -277,7 +277,33 @@ void write_char(int c, int sft_idx)
 
 void write_char_stdout(int c)
 {
-  write_char(c, get_sft_idx(STDOUT));
+  unsigned char scrpos = scr_pos;
+  unsigned char count = 1;
+  unsigned flags = get_sft(STDOUT)->sft_flags & (SFT_FDEVICE | SFT_FBINARY);
+
+  /* ah=2, ah=9 should expand tabs even for raw devices and disk files */
+  if (flags != SFT_FDEVICE)
+  {
+    if (c == CR)
+      scrpos = 0;
+    else if (c == BS) {
+      if (scrpos > 0)
+      scrpos--;
+    } else if (c != LF && c != BELL) {
+      if (c == HT) {
+        count = 8 - (scrpos & 7);
+        c = ' ';
+      }
+      scrpos += count;
+    }
+    /* for raw devices already updated in dosfns.c */
+    if (!(flags & SFT_FDEVICE))
+      scr_pos = scrpos;
+  }
+
+  do {
+    write_char(c, get_sft_idx(STDOUT));
+  } while (--count != 0);
 }
 
 #define iscntrl(c) ((unsigned char)(c) < ' ')
diff --git a/kernel/inthndlr.c b/kernel/inthndlr.c
index e9e9cf8..97f7112 100644
--- a/kernel/inthndlr.c
+++ b/kernel/inthndlr.c
@@ -482,14 +482,13 @@ dispatch:
       /* Display String                                               */
     case 0x09:
       {
-        size_t count = 0;
-        char FAR *bp = FP_DS_DX;
+        unsigned char c;
+        unsigned char FAR *bp = FP_DS_DX;
 
-        while (bp[count] != '$')
-          count++;
+        while ((c = *bp++) != '$')
+          write_char_stdout(c);
 
-        DosWrite(STDOUT, count, bp);
-        lr.AL = '$';
+        lr.AL = c;
       }
       break;